Concrete is freezing again somewhere

In a recent report published by the Ministry of Employment and Labor and the Korea Occupational Safety and Health Agency titled "Major Accidents White Paper – 2023: The Danger is Not Over Yet," concerns about cold weather concrete construction have emerged. On page 35, the document highlights the essential need for quality control in concrete construction under challenging conditions, specifically emphasizing the difficulty of proper concrete curing at temperatures below 5 degrees Celsius. The analysis focuses on the incident that occurred at 3:46 p.m. on January 11, 2022, when a collapse took place at the i-Park Apartments in Hwajeong-dong, Seo-gu, Gwangju. People witnessed the collapse aired live. The rebars stem from the cross-section of the debris and the piles of concrete, with the flurries of snow flying above the remains.

The report states, "In winter, as concrete solidifies and the strength gain slows down, it is essential to ensure an adequate curing period while progressing with construction. Additionally, exposure to subzero temperatures can result in a critical flaw where the concrete freezes during the curing process."

The phenomenon where concrete, not yet fully solidified owing to the winter cold, freezes and then thaws back as temperatures rise is referred to as 'freeze-thaw.' When the moisture within concrete freezes, its volume expands by approximately 9%. Upon melting, the concrete becomes weakened, much like the porous bones of a patient with osteoporosis. It's a simple yet indisputable law of physics. Ignoring this law led to the tragic deaths of six construction workers on-site. However, the person who violated the law of physics and the one who perished as a result are not the same individuals. The person who, in pursuit of greater profits and reduced losses, decided, approved, and pressed ahead to expedite the construction schedule and pour concrete even in subzero temperatures was not one of the fatalities but rather the one responsible for them.

The white paper warns, "When individuals repeatedly face an atmosphere that demands accepting risks, they unknowingly enter into dangers like moths to a flame. This is particularly true in the construction industry, where pressure to shorten project timelines is prevalent." Speaking anonymously after the tragedy, workers at the incident site revealed, "We shouldn't have poured concrete on snowy days. There were instructions to hurry up."

However, the report lacks one crucial element – government accountability. It must be noted that the collapse of all these systems occurred within the national borders where the central government and relevant ministries (Ministry of Employment and Labor, Ministry of Land, Infrastructure and Transport, etc.) manage construction site safety. The document should have questioned why government oversight failed, why the ground reality wasn't known (or if it was, why it was ignored), and why preventive measures were not implemented.

As concrete follows the laws of physics, companies adhere to the laws of profit pursuit. Construction workers find themselves caught between these two laws today. If the government wishes to protect citizens' lives, it must ensure that the laws of physics precede profit-seeking laws. The citizens have entrusted the government with laws and enforcement powers for this very purpose.

As the year-end closes, the weather is growing extremely fickle, with the temperatures reaching an all-time high of November before fluctuating up and down again. This means the unyielding laws of physics will cause hidden moisture in construction sites nationwide to freeze and thaw repeatedly. Somewhere in this country, concrete is freezing again.